- Zou, Fanggeng;
- McWalter, Kirsty;
- Schmidt, Lindsay;
- Decker, Amy;
- Picker, Jonathan D;
- Lincoln, Sharyn;
- Sweetser, David A;
- Briere, Lauren C;
- Harini, Chellamani;
- Network, Members of the Undiagnosed Diseases;
- Marsh, Eric;
- Medne, Livija;
- Wang, Raymond Y;
- Leydiker, Karen;
- Mower, Andrew;
- Visser, Gepke;
- Cuppen, Inge;
- van Gassen, Koen L;
- van der Smagt, Jasper;
- Yousaf, Adeel;
- Tennison, Michael;
- Shanmugham, Anita;
- Butler, Elizabeth;
- Richard, Gabriele;
- McKnight, Dianalee
Pathogenic missense and truncating variants in the GABRG2 gene cause a spectrum of epilepsies, from Dravet syndrome to milder simple febrile seizures. In most cases, pathogenic missense variants in the GABRG2 gene segregate with a febrile seizure phenotype. In this case series, we report a recurrent, de novo missense variant (c0.316 G > A; p.A106T) in the GABRG2 gene that was identified in five unrelated individuals. These patients were described to have a more severe phenotype than previously reported for GABRG2 missense variants. Common features include variable early-onset seizures, significant motor and speech delays, intellectual disability, hypotonia, movement disorder, dysmorphic features and vision/ocular issues. Our report further explores a recurrent pathogenic missense variant within the GABRG2 variant family and broadens the spectrum of associated phenotypes for GABRG2-associated disorders.